Currently our VMWare setup has more than enough power to handle all of our needs in terms of processing power. We have about 30 VMs, 4 of which are file servers. 26 of the VMs are stored on one AX4-5i. The file servers are stored on an old CX300i. We are almost out of space on the CX300i and it is no longer covered under warranty, and therefore I need to come up with a robust solution that allows us to replace the CX300 while allowing enough storage space for future growth. As a school, we have a massive amount of data... at this point, about 6TB for home folders and other network shares and growing continuously.

Some options I have thought about:

Migrate the file-server data to a NAS device, Leave the rest of the virtual environment as is. I would get a lot more storage space.

Purchase a new server with more local storage to host the file-server VMs.

Overhaul the whole virtual infrastructure. We are running ESXi 3.5, which while handling our needs well, is no longer supported. We need to do this eventually anyways, but I am reluctant to mess with something that has generally been very reliable.

What would you do? Are there are other options I should be considering?

So would I be better spending the 4000 Euro on a NAS, or 12000 Euro on 2 servers with enough storage space for all of our VMs (but only 1 year warranty on the midline disks in the servers), and an upgrade to Hyper-V 2012 or VMWare 5.1?

This is where your math is broken. You are comparing a redundant server setup in one case and a non-redundant NAS setup in the other. Keep in mind that...

So, this means that your two servers, one NAS setup (inverted pyramid) is less reliable, by a huge margin, than just running a single server with no redundancy at all. Any redundancy you've built in is fake... it does nothing to protect you but makes you feel safer than you are.

You would cut costs even more and improve reliability dramatically by dropping the NAS and dropping the second server. That you are willing to rely on the NAS proves that your risk profile accepts a single server since that is better, not worse. And since it is faster, cheaper and has lower downtime, you win, win, win on top of being more reliable.

NAS never wins on costs, it just helps in fooling yourself into thinking you've kept up the other factors.

46 Replies

you can add a NAS datastore to esxi server and cold migrate your file server to it. If you go for DAS ,then you wouldnt be able to add another vms to it due to lack of space . as longs as NAS can survive in fileserver IOPS request, i think it will be the better idea.

We have a Synology 1812+ NAS device that we use for backups. Dual NICs. I get about 100MB/sec data transfer across the network when doing a file copy from a client PC to the NAS device, which is better than I get copying the same file from the same client to the file server VM. So performance wise I would suspect to see an improvement moving over to a NAS.

We have a Synology 1812+ NAS device that we use for backups. Dual NICs. I get about 100MB/sec data transfer across the network when doing a file copy from a client PC to the NAS device, which is better than I get copying the same file from the same client to the file server VM. So performance wise I would suspect to see an improvement moving over to a NAS.

When I mentioned NAS, I meant a standalone NAS device, not connected to my virtual environment. It would just host files, no virtual machines. I would migrate all files to the NAS and users would connect directly to it to access their files.

When I mentioned NAS, I meant a standalone NAS device, not connected to my virtual environment. It would just host files, no virtual machines. I would migrate all files to the NAS and users would connect directly to it to access their files.

Ahhhh. That makes more since now. But still I would keep it as a VM. :)

What happens the NAS fails? You have to recover from your backup, and this normally takes a lot of time.

If your hosts fails, you normally have plenty of good options for quick recovery (Replica's\Instant Recovery\Restore)

Hi Aaron,

I agree with you, and I know the benefits of staying virtual. But I have to bear in mind cost as well. I need about 10TB of RAID storage space. That's going to be WAY more expensive than a NAS device... on the order of 3-10X more. As long as I have robust backups, can I justify the cost?

What happens the NAS fails? You have to recover from your backup, and this normally takes a lot of time.

If your hosts fails, you normally have plenty of good options for quick recovery (Replica's\Instant Recovery\Restore)

Hi Aaron,

I agree with you, and I know the benefits of staying virtual. But I have to bear in mind cost as well. I need about 10TB of RAID storage space. That's going to be WAY more expensive than a NAS device... on the order of 3-10X more. As long as I have robust backups, can I justify the cost?

What would be your backup plan for the NAS? What would your recover time be?

You will have to run the numbers to figure out what makes since, but I think you will find that keeping it virtual is the way to go.

Also, I am not sure your costs make since, can you post what your comparing?

What happens the NAS fails? You have to recover from your backup, and this normally takes a lot of time.

If your hosts fails, you normally have plenty of good options for quick recovery (Replica's\Instant Recovery\Restore)

Hi Aaron,

I agree with you, and I know the benefits of staying virtual. But I have to bear in mind cost as well. I need about 10TB of RAID storage space. That's going to be WAY more expensive than a NAS device... on the order of 3-10X more. As long as I have robust backups, can I justify the cost?

What would be your backup plan for the NAS? What would your recover time be?

You will have to run the numbers to figure out what makes since, but I think you will find that keeping it virtual is the way to go.

Also, I am not sure your costs make since, can you post what your comparing?

Synology uses a local backup to USB drive, or to a network share.

A Synology 1813+ NAS with 24TB RAW is about 2000 Euro.

A low end HP server with 12LFF and 8x3TB midline disks will run about 6000 Euro.

A higher end HP server with 25SFF, 20x1.2TB 10K disks will be over 20000 Euro.

Recovery time wouldn't be great... that is a definite downside. Unless, of course, I purchased another NAS and replicated data between them, which is an option with Synology. It uses RSYNC. They also have a High Availability option, but I am wary of instantly replicating file corruption.

I need about 10TB of RAID storage space. That's going to be WAY more expensive than a NAS device... on the order of 3-10X more. As long as I have robust backups, can I justify the cost?

Those Synology boxes are amazing for what they cost, you just have to be comfortable with the idea that if they fail there is no SLA so worst case you need both robust backups and somewhere to restore them to.

It comes down to how important having the data available is - what's the impact if it dies?